can i use gravity pipes when converting to fully pumped?

[rolysatch]

hi

i've got a pumped central heating/gravity hot water system. if i was attempting to convert it to a fully pumped S plan system can i use the 32mm flow and 28mm return of the gravity system for my pumped hot water or should i take this all out and replace it with 22mm?

any advice appreciated

 

[Agile]

Practically speaking you can!

 

[rolysatch]

would there be any disadvantages?

 

[Agile]

Need thicker insulation of the larger pipes.

Greater volume of water to heat up in the pipes which would take perhaps a minute extra when heating and the benefit of that will be lost when the MV closes.

Not really significant though.

 

[gaswizzard]

Need thicker insulation of the larger pipes.

Greater volume of water to heat up in the pipes which would take perhaps a minute extra when heating and the benefit of that will be lost when the MV closes.

Not really significant though.

..........................offset against a re-pipe? , me not think so.

Pipework insulated? , me not think so.

Cost difference between 22mm/28mm insulation = insignificant.

 

[Agile]

When did you last buy 32 mm insulation?

Surely you insulate your heating coil supply runs?

 

[oph]

When did you last buy 32 mm insulation?

Surely you insulate your heating coil supply runs?

FFS Tony what and most likley notch the s h ite out of a few joists to do it

 

[misterdubya]

I suspect Tony has drunk a lot of red wine.

 

[Andygasman2010]

32mm? Really?

Either way just leave it in. Better flow rate, it'll heat up quicker I suppose!

I always leave them in, just make sure they're cleaned out well.

 

[gaswizzard]

Council contracts were 50mm insulation on cold water mains (islington) , WTF were they thinking , 115mm insulation overall for a 15mm supply . fookin idiots. , and yes we had to use unistrut and munson rings for a domestic dwelling utilizing 4 main supplys , madness , pipe clip centres being 150mm , lunacy. .

As said , how would you notch the joists for 32mm insulation (75mm) , more BS Tony , the DIY mob might swallow it.

DIYers note , Agile will not come back on this thread when he realises he is spouting BS , some of us guys work in the real world.

No offence Tony but you need pulling up.

 

[Hugh Jaleak]

Council contracts are spending public money, how some of the specs they dream up ever get passed is beyond me. Good example where I live was the public WC's. Rebuild, yes needed it. I didnt however see the need for a sheet copper roof on the whole block when concrete tiles would have been perfectly adequate and acceptable.....

In answer to the OP's question, I used the original 28mm gravity primaries from kitchen to airing cupboard for the flow/return from new boiler in utility room, then piped back as required in 22mm to feed CH. Works with no problem.

 

[Agile]

If under the floor then only insulate between the joists.

Generally the insulation will be flattened by floorboards so no need to over notch the joists.

But should be insulated where the space is available.

Doesn't everyone?

 

[Agile]

I suspect Tony has drunk a lot of red wine.

No, I brought a bottle of 13% Chilean white wine to the Cu Tu Vietnamese restaurant in E2 this evening. The customer paid for the meal tonight!

Tony

 

[gaswizzard]

If under the floor then only insulate between the joists.

Generally the insulation will be flattened by floorboards so no need to over notch the joists.

But should be insulated where the space is available.

Doesn't everyone?

Are you a qualified plumbing and heating engineer Tony? ..and if so where did you take your training?

 

[Gasop]

If under the floor then only insulate between the joists.

Generally the insulation will be flattened by floorboards so no need to over notch the joists.

But should be insulated where the space is available.

Doesn't everyone?

Are you a qualified plumbing and heating engineer Tony? ..and if so where did you take your training?